Changed plugs, now car is dying instantly after starting it

Discussion in 'SN95 4.6L Mustang Tech' started by Highroller, Dec 7, 2003.

  1. I changed the plugs and cleaned my MAF, and IAC Valve because I was having idling problems.. as I thought one of the plugs was so burnt that it had no electrode anymore...either way I switched them all, bolted everything up, and this is what happens:

    turn key to start position.. then all my needles on my guages go to the right (pinned).. and shoot back to the left.. then it Starts right up, but dies instantly.. feels like it's not getting fuel. what would cause this?? I'm 99% sure everything is connected.. I really didn't disconnect to much to switch the plugs :shrug:

    also, I have some device installed on my car, it came from the dealership and supposidly kills the fuel pump if its being stolen.. I do believe that is what's turning my car off.. for the 1/2 second its starts it sounds good.. then dies.

    I was told by the dealership that I can pull a fuse and it should disable the devise.. I don't have my manual anymore, does anyone have a copy of the fuse box diagram so I can cross-reference it to what mine looks like and try disabling this devise..

    anyone else have any ideas of why my bucket isn't starting
  2. The needles moving all the way to the right and back usually indicates the computer resetting itself - anytime you disconnect the battery it'll do that. As far as the idle goes, doublecheck your connections to the IAC (is the plug in?). I know it sounds simple and you probably already checked, but if the solenoid can't actuate to allow air for the idle, instant stall.


  3. Unplugged it and plugged it in again.. still happening.. it has to be something simple, I've changed these things like 5 times and never a problem..

    now my 03 is going to be sitting in my garage as I send in my $500 payment :bang:
  4. Can you give it gas to keep it running?
  5. What did you clean the maf with? The "fuse" the dealer is talking about is a device in the trunk usually on the drivers side above the tire. It's like a circuit breaker that goes off in case of an accident so fuel delivery stops. That shouldn't be the problem. Did you gap the plugs properly?
  6. If I keep my foot on the gas it will stay running but want to turn off, it will keep coughing kinda and when I take my foot off the gas it turns off

    regarding the gap, I just kept the gapping as it came... wouldn't it start at least even if I is gapped wrong.. the dealer said they come gapped within .30 -.40

    I actually have to push a button everytime or my car will not start, that is the alarm that I was talking about... I will attach a picture of the key fab I have to push and I will attach a pic of my fuse box, maybe you guys can look at yours and see if I have an extra fuse..
  7. Wierd. I know the plug thing sounds silly but I had this problem on a 95 mustang. Put two sets of plugs in it the same day and finally convinced myself that the plugs weren't the problem. Took the car to a dealership and before I got out of the parking lot the service manager came out and said "we'll take those crappy platinum plugs out, put some motorcraft plugs in it gapped at .054" and you'll be ready to go". Problem solved. All this started right after I cleaned my iac and according to the dealer was the reason I fouled 2 sets of plugs in the same day. So if your'e not blown the gap should be .054". I'd start there since it's fairly easy and make sure you don't have any residue (whatever you cleaned your maf with) on your maf. Good luck.
  8. I see you're running n20 so your gap should be low .030s and a heat range cooler so as long as that's the case I guess you can rule that out. I still don't understand about the button your'e pushing. Do you have a pic?
  9. I cleaned them with Electronic's part cleaner.. and the plugs I put in were autolite 103's

    I guess I can take them all out again tomarrow, and make sure there gapped right.. I have seen people's car start with plugs gapped at .30 all the way up to .78.. either way, thanks for all the help.. I will let you know how it works out in the morning. Im still thinking it's wierd about how the guages just go to the right.. this all happens before I even start the car..????? :bang: :mad:
  10. I might be wrong, but could the chip have any effect on his idling issues?
  11. The description your giving really sound like there is something going on with your IAC sensor. Did you make sure the hose that runs from it to your intake is secured well into the intake tube? Ive seen it happen where it looked like it was in the intake tube well, but after adjusting it on that end the car ran fine. Also, is there any chance you IAC just went tottally bad for some reason? I guess it could happen, but who knows.
  12. I guess my IAC could of gone bad.. I have an extra so I will try it tonight.. I'm going to switch it back reset my computer..

    another thing is now there is a red light on my battery... just my luck but I'm assuming its going to go dead... maybe something electrical is draining my battery

    also I took my chip out, just in case.. same problem so I put it back in..
  13. Maybe I just read the post too quick, but I get the impression your gauge needles are pegging out every time you go to start the engine. If you’re not disconnecting the battery and get needle peg, sounds like an electrical problem.

  14. thats what I am thinking... I called Ford and they told me there is a ford relay I can take out that will disable the alarm..

    are the ford relay's the black things...

    here is a pic of my fuse box
  15. I had this same situation happen to me. Cleaned up the IAC and swapped out plugs and after I fired it up, it would quit. Drove me nuts.
    Pull the IAC and either re-clean it or change it out completly. 99% sure thats where your problem is. That damn thing can shut the engine down no problem when its not "just" right.
  16. Even though you may have cleaned the IAC it may have gone completely bad. I'd bet my left nut that is the problem. Sorry for the visual but I'm completely sure that is your problem.
  17. Well the reason I go on these boards it to get your guy's idea's.. and I want to seriously thank all of you..

    I managed to finally bypass the alarm thing.. and the problem still exists.. so tonight Im going to switch IAC's and see if that helps

    also.. offtopic but 2 of my plugs were green.. is that signs of a lean condition
  18. Well I switched the IAC valve, and the same problem is still there..

    I don't see how, but maybe I switched the coil packs around on the wrong spark plugs?? I don't see how cause they really can't move around.. I mean to stretch one to another COP and not notice would be hard

    im going to go buy new plugs, and make sure there gapped at .54 and try it then.. if that fails... I'm pushing my car in Lake Mead :bang:
  19. One of my friends did the same thing that you did, minus cleaning his IAC. Once he put it all back together with his cleaned mass air meter it wouldn't run. His Mass Air Meter was bad. We swapped them out with another friend's MAF and it ran fine. :shrug:
  20. put new battery in yesterday, solved the guages going all the way to the right... but problem is still there...

    I thought spraying the sensor with electronic parts cleaner can't hurt anything..

    I'm hesitant on buying a new MAF, cause now I have bought a IAC, 2 sets of plugs, battery (had to buy anyway) and a crap load of tools

    how much do you think a new MAF costs.. and should I get it from FORD